Water leak damage

[DCW]

Camping world sold me a 2018 Alante with multiple water leaks. I found one but failed to find the water intrusion from the passenger side mirror for several months. While I think i fixed the mirror leak after a couple of tries, I now have the floor damage to repair. I've scraped the rotten wood back to good wood and sprayed the area with bleach solution. My intent is to cut a piece of plywood approximately the same size and fill the gaps with wood putty.

Anyone have a better idea or additional steps to take.

[RogerR]

If you can get below the floor I would reinforce the area with extra support beams, preferably, pressure treated and inspect all adjacent areas for hidden damage.

I would cut out any damaged boards completely well into good wood in case the damage is not surface visable. Any joints should be supported on both sides of the joint. Use of glue between the supporting beams and new floor is good idea plus plenty of screws.

[DCW]

Thanks Roger, the plywood floorboard is the only wood around. The subfloor is styrofoam with plate metal welded to the aluminum frame. Still have the drying with dehumidifier and cleaning up the rest of the damaged plywood. then i'll lay down the replacement wood.
Thanks for the advice